Spring Boot Limits and Migrating to Thymeleaf

Why Boot 3 Breaks Tiles

• Executable jars cannot reliably serve JSPs (a Jasper limitation, not Spring).
• Spring Framework 6 removed TilesConfigurer and TilesViewResolver.
• Result: Tiles officially ends at Spring MVC 5 + war + Tomcat 9.

Migration Path to Thymeleaf

1. Replace tiles.xml with a layout.html using Thymeleaf Layout Dialect (layout:decorate, layout:fragment).
2. Convert each body JSP to a fragment HTML file; header/footer/menu become th:fragment includes.
3. Controllers stay identical - they already return logical view names.
4. Package as executable jar; delete Jasper and Tiles dependencies.

Interview Answer

Tiles versus Thymeleaf: Tiles is XML-configured JSP composition for Spring 5 legacy apps; Thymeleaf is HTML-native, Boot-friendly and actively maintained. Recommend Thymeleaf for anything new.

Key Points

• Do not start new Boot 3 projects on Tiles.
• Migration is mostly view-layer; controllers survive.
• This tutorial repo stays on Spring 5 on purpose.